In a medium skillet over medium heat, heat oil. Add scallion whites, season with salt and pepper, and cook, stirring, until whites are just starting to brown, 2 minutes. Add scallion greens and cook 1 minute more. Remove from heat.

Spread refried beans over half the tortilla, then top with cooked scallions. Fold tortilla over.

Return skillet to medium-low heat and place filled tortilla in skillet. Cook until beans are warmed through and tortilla is golden brown on both sides, 3 minutes per side.